Improvement in saw-mills



UNITED STATES PATENT Gerace.

IMPROVEMENT IN SAW-MILLS.

Specification forming part of Letters Patent No.v 48,804., dated July 18, 1365.

To all whom it may concern:

Be it known that I, JosnPn Fncirnn, of Gavetown, in the county of Washington and State of Maryland, have invented certain new and useful Improvements in the Manner of Hanging Saw-Hill Saws, so as to make them wear evenly throughout their entire length, and I do hereby declare the following to h o .a full, clear, and exact description thereof, reference being had to the accompanying drawings, making a part of this specifica-tion, in A which- Figure I represents a saw-pitnian, showing the wrist-pin or crank-pin bloclr` in one of its positions and the follower and keys for holding it. Fig. 2 represents the sume pitman with the block and follower in their other position for changing the working part of lhe saw. Figs. 3 and 4 represent detached views of the blocks and followers removed from the pitman.

Similar letters of reference, where they ocour inthe separate figures, denote like parts in all cases.

In saw-mills as ordinarily constructed and used the saw wears away in a rounded or concave form, and the upper end of the saw, not cutting in the timber, is not worn away, and consequently has to be liled ed', which requires much labor and loss of time, as well as expense in the waste of saws.

'Ihe object ofmyinvention is to obvia'te this objection by a che-ap and simple device connected with the pitinnn, and by means of which the saw-gate may he raised or lowered in the guide-posts, so as to utilize the whole cuttingedge of the saw, cause it to wear away evenly, and thus avoid so much ling as is now done and my invention consists in combining with an ordinary saw-pitman a crank-block and follower that can be changed one for the other and then keyed fast, so as to shift the workin g portion of the saw, and thus make it wear away uniformly.

To enable others skilled in the art to make and use my invention, I will proceed to describe the same with reference to the drawings. y

A represents a pitman, in the lower end ot which is made a mortise of sufficient length to receive both the wristpin or crank-block B and the follower C, and which, when adjusted, are firmly held therein by the keys or wedges D D', passing through at right angles to the mortise.

The wrist-pin or crank-pin block B is fur nished with a wrist-pin a, and has an open mortise, I) b, in each of its ends, and to preserve its shape or form may be incased in metal e,if made of wood; hutif made of metal, then this would not be necessary.

The follower C may be similarly made of wood or metal, or parts et' each, and has also open mortises (I in each of its ends, so that whichever of the ends of the crank-pin block and of the follower are placed together the two open or half mortises will form a complete mortise, through which thekey or wedge D is driven, and thus holds both, while the other key or wedge, D', passes through one of the open or half mortises of one or both ofthe opposite ends, and thus firmly holds them there to the pitman. When the block and follower occupy the positions shown in Fig. l the lower end of the saw is doing the work. When changed and in the position respectively as shown in Fig. 2 the upper end ofthe saw is doing the work, and thus by changing the crank-pin block the saw is worn away uniformly throughout its entire length.

Having thus fully described my invention, what I claim therein as new, and desire to secure by Letters Patent, is-

In combination with a saw pitman, the changeable crank-pin block and follower with their keys or wedges for the purpose of shifting the working partof the saw,and thus cansing it to wear away uniformly throughout its length and avoid the necessity and loss of so much tiling, as herein described and represented.

J OSEPH FECKER.

Witnesses:

DANIEL D. SrEsAnD, GEORGE BEARD. 

